.\"
.\" Copyright (c) 2013 Robert N. M. Watson
.\" All rights reserved.
.\"
.\" This software was developed by SRI International and the University of
.\" Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
.\" ("CTSRD"), as part of the DARPA CRASH research programme.
.\"
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.\" modification, are permitted provided that the following conditions
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.\"    notice, this list of conditions and the following disclaimer in the
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.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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.Dd May 15, 2020
.Dt PROCDESC 4
.Os
.Sh NAME
.Nm procdesc
.Nd process descriptor facility
.Sh DESCRIPTION
.Nm
is a file-descriptor-oriented interface to process signalling and control,
which supplements historic
.Ux
.Xr fork 2
and
.Xr kill 2 ,
primitives with
new system calls such as
.Xr pdfork 2
and
.Xr pdkill 2 ,
.Nm
is designed for use with
.Xr capsicum 4 ,
replacing process identifiers with capability-oriented references.
However, it can also be used independently of
.Xr capsicum 4 ,
displacing PIDs, which may otherwise suffer from race conditions.
Given a process descriptor, it is possible to query its conventional PID using
.Xr pdgetpid 2 .
.Sh SEE ALSO
.Xr fork 2 ,
.Xr kill 2 ,
.Xr kqueue 2 ,
.Xr pdfork 2 ,
.Xr pdgetpid 2 ,
.Xr pdkill 2 ,
.Xr wait4 2 ,
.Xr capsicum 4
.Sh HISTORY
.Nm
first appeared in
.Fx 9.0 ,
and was developed at the University of Cambridge.
.Sh AUTHORS
.Nm
was developed by
.An -nosplit
.An Robert Watson Aq Mt rwatson@FreeBSD.org
and
.An Jonathan Anderson Aq Mt jonathan@FreeBSD.org
at the University of Cambridge, and
.An Ben Laurie Aq Mt benl@FreeBSD.org
and
.An Kris Kennaway Aq Mt kris@FreeBSD.org
at Google, Inc.
